This invention relates to processing glass and dispersion-strengthened glass materials.
Dispersion-strengthened composites are materials in which crystalline reinforcement particles, e.g., alumina or zirconia, are dispersed throughout a glass matrix, e.g., a feldspathic glass. The crystalline particles improve the elastic modulus, strength, and toughness of the glass; the degree of improvement is related to the volume fraction and particle size of reinforcement added. The size of the reinforcement particles typically is on the order of 10-50 .mu.m.
Maclean et al., British Dental Journal, 119: 251-67 (1965) has suggested using alumina-filled porcelain composites of this type to form dental prostheses, e.g., crowns. In dental laboratory practice, composites generally are prepared by first forming an aqueous slurry of the glass and reinforcement powders. The slurry is then stacked on a substrate and vibrationally compacted. The compacted article (called "Greenware") is then fired to form the final composite.